Yep, already been mulling it over. A few points of Ukrainian consideration: Brigades seem to have 'home bases'. Therefore these bases [urban areas] could have a supply point with a limited radius. Each Brigade will have a static 'HQ/Depot' unit at their homebase that contains Support Squads. Bombardment of these units can cause Supply Reductions. Operations too far from the home base will suffer. Maybe. Still noodling over it.This is relevant for how you handle rail, supply points and supply radii.
Russia might could have the same system. It seems they have trouble with supply lines. Reports are the Russians are looting stores for food. After all, they didn't plan on this, they thought Ukraine would fold if pushed.